Optical microcavity

About: Optical microcavity is a research topic. Over the lifetime, 2599 publications have been published within this topic receiving 72125 citations. The topic is also known as: optical microcavities.

Direct evidence of open ray orbits in a square two-dimensional resonator of dye-doped polymers.

Abstract: Lasing has been observed in optically pumped 4-dicyanomethylene-2-methyl-6-(p-dimethylaminostyrl)-4H-pyran-doped poly(methyl methacrylate) square-shaped micropillars that allow four-bounce closed and open ray orbits with internal incident angle θinc>θc (the critical angle for total internal reflection) and with the associated surface waves that emit at the four corners We also detect strongly TE-polarized and spatially varying emission from the square sidewalls that is due to leaky open ray orbits with θinc near but less than θc for two of the four bounces By selectively pumping the square microcavity with a stripe-shaped beam, we excite different four-bounce ray orbits

Dynamical optical tuning of the coherent phonon detection sensitivity in DBR-based GaAs optomechanical resonators

Abstract: We present a detailed time-resolved differential reflectivity study of the electronic and the coherent phonon generation response of a GaAs optical microcavity after resonant picosecond laser pulse excitation. A complex behavior is observed as a function of laser--cavity-mode detuning and incident power. The observed response is explained in terms of the large dynamical variations of the optical cavity-mode frequency induced by the ultrafast laser excitation, related to the optical modulation of the GaAs-spacer index of refraction due to photoexcited carriers. It is demonstrated that this effect leads to a strong optical dynamical tuning of the coherent phonon detection sensitivity of the device.

Performance of organic light-emitting devices using spin-dependent processes

Abstract: The maximum luminous efficiency of organic light-emitting materials is increased through spin-dependent processing. The technique is applicable to all electro-luminescent processes in which light is produced by singlet exciton decay, and all devices which use such effects, including LEDs, super-radiant devices, amplified stimulated emission devices, lasers, other optical microcavity devices, electrically pumped optical amplifiers, and phosphorescence (Ph) based light emitting devices. In preferred embodiments, the emissive material is doped with an impurity, or otherwise modified, to increase the spin-lattice relaxation rate (i.e., decrease the spin-lattice time), and hence raise the efficiency of the device. The material may be a polymer, oligomer, small molecule, single crystal, molecular crystal, or fullerene. The impurity is preferably a magnetic or paramagnetic substance. The invention is applicable to IR, UV, and other electromagnetic radiation generation and is thus not limited to the visible region of the spectrum. The methods of the invention may also be combined with other techniques used to improve device performance.

Coherent control of quantum-well excitons in a resonant semiconductor microcavity for high-speed all-optical switching

Abstract: Coherent control of excitons in quantum wells embedded in a resonant planar semiconductor microcavity versus in quantum wells without the cavity at high repetition rates is investigated theoretically to determine the practical constraints for application in high bit-rate optical switching. It is shown that /spl pi/-shifted pulse pairs are optimal to coherently populate and depopulate the QW on the 100-fs timescale. For the cavity-free case, the small optical nonlinearity will require devices incorporating /spl sim/100 quantum wells; the resonant enhancement of the confined mode for the case of the cavity leads to an effective increase in the optical nonlinearity and thus a reduction of the required number of quantum wells to /spl sim/10. In addition, switch architectures that avoid interferometers, and thus will have superior temperature and mechanical stability, based on the microcavity are proposed. We believe that although room-temperature operation of a 100-Gb/s switch based on this principle may be difficult, operation at liquid-nitrogen temperature should be feasible.

Exciton-photon interaction in a quantum dot embedded in a photonic microcavity

Abstract: We present a detailed analysis of exciton–photon interaction in a microcavity made out of a photonic crystal slab. Here we have analysed a disc-like quantum dot where an exciton is formed. Excitonic eigen functions in addition to their eigen energies are found through direct matrix diagonalization, while wavefunctions corresponding to unbound electron and hole are chosen as the basis set for this procedure. In order to evaluate these wavefunctions precisely, we have used the 6 × 6 Luttinger Hamiltonian in the case of hole while ignoring bands adjacent to the conduction band for electron states. After analysing excitonic states, a photonic crystal-based microcavity with a relatively high quality factor mode has been proposed and its lattice constant has been adjusted to obtain the prescribed resonant frequency. We use a finite-difference time-domain method in order to simulate our cavity with sufficient precision. Finally, we formulate the coupling constants for the exciton–photon interaction both where intra-band and inter-band transitions occur. By evaluating a sample coupling constant, it has been shown that the system can be in a strong-coupling regime and Rabi oscillations can occur.